Various fiber optic catheter devices have been proposed for use in blood vessels. These prior devices generally utilize an expandable balloon or other means to occlude the vessel while a clear fluid flushes downstream of the balloon to provide a clear operating region for the use of an optic system. This optic system can be a viewing system, a laser light transmitting system, or a combination of both.
Unfortunately, these prior devices have shortcomings. For example, none of the prior devices provide means for introducing an oxgyen bearing liquid downstream of the balloon and the clear operating region. However, if the supply of oxygen is interrupted for more than a few seconds, the tissue downstream of the balloon can suffer irreparable damage. Introducing a stream of flushing fluid such as an oxygen bearing liquid past the optic system is not always satisfactory because most oxygen-bearing liquids are opaque. Also, such a stream could wash debris away from the operating region before the debris could be collected and removed, e.g. with suction or flushing.
Even where a stream of flushing fluid is not present, the prior devices make no provision to prevent blood from diffusing into the flushing fluid in the operating region. Nor is there any provision for the sure recovery of any debris that may be liberated from the walls of the blood vessel. With these prior devices, any such debris can drift away from the device and be carried away by the flow of blood.
What is needed is a catheter device which avoids the deficiencies of the prior art and provides a clear and safe operating region within a blood vessel, while providing an oxygen bearing liquid to the tissue downstream of the device. It would also be desirable if such a device maintained a clear operating region and provided for expeditious recovery of any debris that may be generated. The present invention satisfies these desires.